Mechanoluminescence integrity checks for wind turbines
A technology for visual detection of structural defects in the composite parts of operational wind turbines
Benefits
- Repeatable due to its basis on elastic deformation
- Contactless, visual detection
- Real time detection and continuous monitoring
- No power supply needed for equipment
- Detection available over a large surface area
- Unaffected by electromagnetic waves
- Detects a range of stresses (friction, impacts, cracks, etc.)
Issue
Real mechanical stress on materials / structures during their lifecycle are often difficult to measure. The effects are generally not directly visible, or are visible too late. Non-destructive testing methods can be used to detect anomalies after an event but cannot be used for continuous monitoring before the appearance of damage to the material. Different types of sensors allow certain parameters to be measured in real time (stress gages, etc.) but these are external components often positioned on the surface and only measuring one type of mechanical stress at one particular point.
Solution
We have developed a new type of elastic-mechano-luminescent (EML) product that is able to emit a luminous signal proportionally to a mechanical stress: compression, flexion, stretching, torsion, impact, friction, etc.
This also allows continuous monitoring of the repeated mechanical stresses suffered by a structure, object, or film. The product functions similarly to piezoelectric systems but provides visual detection in real time, over large surface areas, with no contact required. This new product can be integrated as a film or surface coating applied to the material to be monitored, or as an additive to the mass, particularly for composite matrices (associated with fiber optics).
We have imagined some of the first areas of application for EML materials. For example, in the field of structural health monitoring for preventative maintenance:
- Detecting invisible faults
- Detecting impacts or delamination (composites) in aeronautics, wind power, etc.
- Contactless torque measurement in rotating machinery
- Painting to prevent cracks in the structure of buildings
- Visual marking of the distribution of stresses in a metal part
Other applications:
- Pressure sensing matrix (e.g. smart floors)
- Sensing strain distribution in bones
- Smart textiles